I read with great interest the letter by Calderon et al., who clearly described effectiveness of hyperbaric oxygen therapy (HBOT) for refractory ischemic ulcer at the ileorectal anastomosis in Crohn's disease (CD). I congratulate them on their efforts in achieving a favorable long-term outcome. I would like to share my experience of HBOT for perianal CD (PCD). In addition, I discuss recent trials of HBOT for PCD.